The present invention generally relates to hard tonneau covers for pickup truck beds and more particularly pertains to the mechanism and hardware for mounting such devices to a truck.
As more and more pickup trucks are being purchased and used as primary transportation, items often end up being carried in the cargo bed that should more properly be secured from theft and protected from the elements. Tonneau covers, especially hard tonneau covers afford such protection and security and additionally enhance fuel mileage by smoothing out the air flow over the rear part of the vehicle. Additionally, many find an aesthetic appeal in covering up the cargo bed of a truck.
Hard tonneau covers are typically constructed of fiber reinforced resin, have a high quality finish to match the rest of the vehicle and form a weather tight seal about the top of the cargo bed's sidewalls. The covers are typically hinged at the front so as to tilt upwardly and are latched and lockable at the rear. Telescoping gas struts are used to hold the cover in its open position.
A disadvantage associated with many heretofore known covers is the need to drill holes in the truck's toprails in order to mount the cover thereto. Perforating the sheet metal is especially onerous because more than simple hand tools are thereby needed during installation, any miscalculation in positioning the holes is substantially irreversible and unless special steps are taken to protect the metal that is bared, rust will eventually develop. Another significant problem associated with drilling holes in the truck is the fact that many lease contracts specifically forbid such modifications and in view of the substantial costs that would be incurred in welding up each hole, refinishing and painting the bodywork, most lessees would effectively be forced to purchase the vehicle at lease end. In view of the present popularity of leasing, the desirability of fitting tonneau covers to pickup trucks poses a significant problem.
Hard cover systems are known that obviate the need to drill holes by employing clamps that engage the toprails to secure the hinges, the struts and the locking mechanism. However, such systems still suffer from the need to precisely position the various components along the toprails in order to allow the various components to properly cooperate with one another. Moreover, the wide tolerance variations found on many pickups further complicates the installation.
Finally, an additional problem encountered in the installation of heretofore known cover systems is inherent in the fact that many truck manufacturers use surprisingly thin sheet metal in the construction of their vehicles. Consequently, the substantial loads that may be imposed by the cover on the top rails, especially by the hinges and struts, may cause the top rails to distort to the point where the cover no longer lines up with the latching mechanism, or eventually to the point of structural failure.
A hard tonneau cover mounting system is therefore needed that is simple to install, that requires no holes to be drilled and that minimizes the loads imposed upon the truck's top rails.